Circuit interrupter



May 4, 1 954 H. P. SCHNEIDER CIRCUIT INTERRUPTER Filed July 10, 1952INVENTOR. Hana 1 6'0 neider fill r-n57 Patented May 4, 1954 UNITEDSTATES PATENT OFFICE CIRCUIT INTER-RU? TER Application July 10, 1952,Serial No. 298,108

Claims. 1

This invention relates to circuit interrupters and especially pertainsto a combination fuse cutout. and load. break. switch construction.

It is an object of the present invention to provide a circuitinterrupter comprising in combinationv a conventional fuse link and aload break portion whichv are positioned in a cooperative arrangement.with the. bore of an arc-extinguishing. cartridge unit, which cartridgeis readily inte-rchangeable with conventional circuit interruptercartridges.

It is a specific object of the present invention to provide aninterchangeable cartridge for a circuit interrupter having containedwithin its bore auxiliary load break contacts, one of said contactsbeing in flexible electrical connection with a. conventional fuse linkconnected with line, and the other contact being connected through aconducting. ferrule on the cartridge to complete the electricalconnection with line; the cooperating elements of. the cartridge beingarranged to provide both an overload protective device and a means fordisconnecting a line under load conditions which may be restored fornormal closed circuit operating conditions without deleteriouslyaffecting the fuse link.

A-n embodiment of the invention is disclosed in the accompanyingdrawing, in which Fig. 1 is a side elevation of the invention showingthe combination fuse cutout and load break switch in normal operatingposition.

Fig. 2 is a fragmentary View of a portion of the operating structuredisclosing in detail, the external contact-making means.

Although the novel interrupter cartridge may be interchangeable withpractically any conventional fuse cutout tube, the accompanying drawingdiscloses the preferred arrangement, wherein the device comprises upperand lower stationary terminals indicated generally by the referencecharacters l and 2 which are suitably mounted in spaced. relationshipupon an elongated insulator 3. The insulator is supported from anysuitable support. by means of bracket 4. The novel interrupter cartridgeassembly 5 comprises a tube member 5 joining the terminals I and'z. Thetube is preferably constructed of a. fiber-lined Bakelite structure aswill be hereinafter described. The cartridge assembly 5 may be securedin position to a bracket 1 by means of a set screw 8 and a clamping nutand bolt assembly 9. The cartridge 5' and its supporting bracket l arepivotally supported at one end of a bifurcated hinge member 1-0 by meansof a pivot pin H.

The hinge member In terminates in an eyelet portion l2 which facilitateswithdrawal and as sembly of the cartridge with a hook stick (not shown),as will hereinafter be explained. The hinge member is detaohably andpivotally positioned on the hook-like portion l3 of the lower terminalmember 2 by means of a trunnion pin It. The lower contact I5 iscomprised of a series of leaf springs, which also serve to bias thehinge member If) in a counterclockwise direction about the trunnion M.It will be apparent that the above-described structural arrangementprovides a double pivoted assembly to permit downward and outwardrocking motion, which will permit dropout disconnection of the cartridge5 from contact with the upper terminal 1 either on rupture of the fuselink or on disconnection as will be described. along with the operatingdescription of. the invention.

The upper terminal member I may consist of a structure specificallyillustrated in Fig. 2 and comprising spaced resilient contact arms I6which have been specifically illustrated and described in Patent No.2,331,846, issued on October 12, 1943, to W. O. Schultz, and assigned tothe same assignee as is the present invention.

The contact arms [6 are spaced apart and are held in their relativeposition by a clamping member H. The resilient arms it are slightlyoutwardly flared and are formed with downwardly turned hook-likeportions [8. The hooklilze portions iii are adapt-ed to normally receiveoutwardly projecting ears or arms It integral with the cartridgeassembly 5. Both the upper and lower contacts I and 2,. respectively,provide a means of biasing the cartridge towards downward and outwardrocking motion. Suitable electrical connection to the terminals is madethrough the connectors 20 and M respectively.

The novel cartridge assembly 5' comprises, in detail, the tube 6normally joining the terminals i and 2. The tube is preferablyconstructed of a fiber-lined Bakelite structure. The fiber liner 25' ispreferably of arc-extinguishing material that will act to quench andde-ionize any arcs occurring within the bore of the tube 6. The sleeve26 of Bakelite or other suitable material, is utilized. as a means ofadding strength to the elongated tube. The upper end of the cartridge 5is fitted with a conducting. metallic ferrule 21 which. acts toelectrically connect the upper terminal to the various componentscontained within the bore of the tube. The ferrule 21 is provided withan integral bracket member 28, which is adapted to receive a pivot pin29. A manipulating eyelet 3'0 is pivotally mounted upon the pin 29. Theeyelet 30 is provided with a shoulder portion 3|, which is engaged by abiasing spring member 32. The eyelet 3i) is thereby normally biasedtoward rotationv in a counterclockwise direction. A tongue, or latchingmore ber 33, integral with the eyelet, protrudes into the bore of thetube 5 through a flared opening 34 in the wall of the ferrule 2'].

The load break portion of the interrupter comprises a truncatedconical-shaped arcing contact 35 which normally engages the tongue 33 ofthe eyelet 30, and is normally held in electrical en gagement with thebore surface of the ferrule 21. A stud member 33 extends from the uppersurface of the contact 35, and is threadingly engaged with an insulatingfollower rod 31. The follower rod may be comprised of a material such asfiber or Lucite. Both of these materials will act to quench andextinguish arcs, and will not carbonize. The opposite end of thefollower rod 31 is provided with a stop 38, which may con sist of athreaded bolt and washer combination, as shown, or a bolt with a headportion of a diameter large enough to provide a stopping means with theupper end of the ferrule 2?. The upper end of the ferrule is reduced indiameter to receive a protective removable cap 39 which may be plasticor of any suitable material capable of being molded or drawn to anelongated cup-likc member. This cap 39 acts as a means for protectingthe working parts from the elements. The cap 3.! is made removable inorder to permit access to the operating elements of the cartridge.

The opposite end of the movable contact 35 is fastened to a flexiblespring tensioned conducting lead member 40 through a terminal member 41.The opposite end of the conducting lead it ter minates in a terminalmember 42. The members 4! and 42 are normally biased towards one anotherby a helical spring 43 positioned circumjacently of the conducting lead46. The member 42 is adapted to receive one end of a conventional fuselink 44. The fuse link 44 may be re" leasably fastened, to the member 42by means of a threaded contact 45 joining a contact member 46 projectingfrom the member 42 by means of a machine screw 41. However, it will beobvious that any of many releasable arangements may be provided tofunction equally as well. For instance, the contact 45 of the fuse link44 might be threaded to engage a threaded opening in the member 42 (notshown).

The fuse link 44 may take any of the usual forms and is provided with afusible section 48 having a conducting leader 49 extending therefrom.The leader 49 extends downwardly through the bore of the tubes 6 andupwardly through the bifurcated hinge member if! to a bindingpostterminal 58 provided with a thumb nut 51 screwed on a threaded pin rigidwith the hinge member Ill.

Thus, the entire operating assembly contained within the bore of thetube 6 is held in tension against the resilient action of the helicalspring 43 by fastening the free end of the leader 49 on thec1amping-post 53 with the aid of the thumb screw 5|. The upper, or loadbreak portion of the mechanism, as stated previously, includes thetruncated conical-shaped arcing contact 35 which is engaged at itstruncated portion by the latching tongue 33, which also forces thecontact towards good electrical engagement with the conducting ferrule27. Fig. 1 illustrates the novel co-operating assembly in its normaloperating position as above described. Electrical connection is providedthrough the resilient contact arms I6 of the upper terminal member I tothe conducting ferrule 2i, through the contact 35 attached to theconducting leader 43, and thereby continued through the fuse link 44 tothe hinge member 10 of the lower terminal 2.

The device operates as follows: When the device is to be operated as aload break switch, a hook or switch stick (not shown) is inserted in themanipulating eyelet 30, and is pulled in a downward and outwarddirection. The downward motion on the eyelet 30 will cause it to pivotin a clockwise direction, thereby releasing the engagement between thelatching tongue 33 and the contact 35. Since the contact is biased in adownward direction, as shown in Fig. l, by the helical spring 33circumjacent to the conducting lead 49, the electrical connectionbetween the contact 35 and the ferrule 2'! will be severed. Any arcsthat may be created from disengagement of these contacts under loadconditions will be drawn within the bore of the tube 6, where they maybe properly extinguished. Since the tube 6 is lined with a fiber liner25, the arc will act upon the bore of this liner and will be rapidlyquenched and. tie-ionized. As the contact continues to move in adownward direction, it will carry along its follower rod 37, which rodwill act to confine the are within the bore of the tube where it may beproperly extinguished. The follower rod 3? may be made of horn fiber orLucite, or other suitable material which do not carbonize under arcingconditions.

Concurrently with the separation of the movable contact and ferrule 2'5,and preferably momentarily thereafter, the cartridge assembly '5 willpivot downwardly and outwardly about its pivot points i! and i l on thehinge member ID as tension is released on the leader 49 by separation ofthe contacts. It will be apparent that the latching arrangement providedbetween the contact ears Ii,- on the ferrule 2! and the hooklike portion58 of the resilient contacts l6 will be released to permit outwardmotion about the trunnion M of the lower terminal member 2. Theoperating assembly contained within the bore of the cartridge 5 will beprevented from. withdrawing completely from the bore by engagement ofthe stop 38 on the follower 31 with the upper surface of the ferrule 27.

When it is desired to again establish electrical connection between theterminals l and 2, the cartridge assembly is reset in normal operatingposition. This may be done by inserting the hook portion of a switchstick in the eyelet i2 and removing the unit from the hook portion l3 ofthe lower terminal member 2. The operator first removes the cap 39 fromthe upper extremity of the cartridge assembly 5. As shown, the capthreadingly engages the ferrule 2'5, but may be a press fit with theferrule if so desired. After the cap is removed, the stop 38 is graspedand pulled in a tensioning direction against the biasing action of thespring 43 to reset the latching tongue 33 of the eyelet 33 in engagementwith the movable contact 35 to the position shown in Fig. l. Theprotective cap 39 is replaced on the cartridge, and the assembly isreset with the trunnions l 4 inserted in the hook-like portion i3 of thelower terminal member 2. The switch stick (not shown) is now inserted inthe eyelet 30 of the cartridge, and the cartridge assembly 5 is pivotedabout the trunnion i l in a counterclockwise direction to engage theears [9 with the hook-like portion 13 of the resilient contact 16 of theupper terminal member I. The unit 5' is. not established. in normaloperating: position.

The operation of: the apparatus under overload is as follows: When anoverload occurs, the fuse link Mi is ruptured at the fusible portion 58and the helical spring it acts" to draw the ruptured. sections apartfrom one another. Any arcs created under this overload condition will beproperly extinguished within the confines of thetube: 6, asabove-described in connection with disconnection' under nor-.nal loadconditions. The: lead-r er 49 is expelled downwardly and the weight ofthe fuse tube and its associated parts,aswell1 as release of the springtension, bias the cartridge toward downward motion. It is apparent,therefore, that when the fuse link is ruptured, the" cartridgepositioned on dual pivot members H and M will rock downwardly andoutwardly to detach itself from the latching hook like: portion [-8 ofthe resilient members it of the upper terminal members i. The cartridgewith its-ruptured link, will drop downwardly to hang in a verticalposition away from the upper contact (not shown).

In the blown position it is obvious that the cartridge assembly 5 may belifted from the hook supports it by means or" a switch stick; co-actingwith the eyelet portion ii? of the hinge member H). The fuse tube maythen be re-fused at the junction of the contact 48' and G5, withelectrical connection being completed as shown in Fig. 1, andparticularly described in connection with the above load break operatindescription.

It will be seen that a novel form of a circuit interrupter has beenprovided which has both automatic and manual operation responding to anoverload in an automatic manner and capable of being operated manuallyto interrupt the circuit under load without damage to the cutout. It isalso to be seen that the composite fuse link is not destroyed when thecutout is manually opened under load as the same fuse'link is again putin service as described in the above.

I claim:

1. In a circuit interrupter including first and second stationaryterminals, an interrupter assembly having an arc-extinguishing chamber,said assembly normally electrically connecting said terminals andcomprising two main interrupter portions contained within said chamber,said portions being normally in series electrical connection with oneanother, one of said portions being in electrical connection with saidfirst stationary terminal, and the other of said portions beingelectrically connected to the second terminal, the first-mentioned ofsaid interrupter portions comprising separable normally closed switchcontact means adapted to be separated to open position under normal loadconditions, the other oi said main interrupter portions comprising afusible member adapted to rupture under overload conditions.

2. An interchangeable interrupter assembly for a circuit interrupterincluding first and second stationary terminals, said interrupterassembly normally electrically connecting said terminals and comp-risingan elongated insulating tubular member having an arc-extinguishingchannel substantially coextensive therewith, two main interrupterportions contained within said channel and normally in series electricalconnection with one another, one of said portions being adapted forelectrical connection with the first of said stationary terminals andcomprising separable normally closed switch contact means adapted to beseparated. to open position under normal. load 6. conditions, the; otherof. said main interrupter portions being arranged. for electricalconnection with said second" terminal and comprising a fusibl'e= memberadapted to rupture under overload conditions.

3. An interchangeable interrupter assembly for a circuit interrupterincluding first and second stationary terminals, said interrupterassembly comprising a tubular member including an arcextingnishingchamber substantially coextensivetherewith, one end. of said tubularmember being arranged for releasable pivotable engagement with the firstof said stationary terminals and having a conducting member beingarranged for latching: engagement with: said second stationary terminal,two maininterrupter portions contained within: said chamber beingnormally in series: electrical connection with one another biasedtowards circuit interruption, one of said interrupter portions includinga movable arcing contact normally in electrical engagement wit said.conducting member, manually operable restraining means yieldinglyholding said movable contact in electrical engagement with saidconducting. member, the other or said portions contprising: a fusiblemember adapted to rupture under overload conditions and arranged forelectrical connection with said first stationary terminal'.

i. A circuit interrupter including first and second stationaryterminals, an interrupter assembly normally electrically connecting saidterminals and comprising in combination an insulating tube pivotallypositioned on said first terminal. and: having an arc-extinguishingchannel substantially coextensive therewith, two main interrupterportions: located within said channel and normally electricallyconnected with one another, one of said portions comprising switch meansandv the other portion comprising a fusiole means, said switch meanscomprising a fixed contact adapted: to bereleasably engageable with saidsecond terminal, a movable arcing contact slidable within said channelnormally elect -ically engaging said fixed contact, spring meansslidably biasing said movable contact towards electrical disengagement,and manually operable re straining means normally holding said contactsinelectrical engagement, said fusible means comprising a fuse linkadapted to rupture under overload and electrically connecting saidmovable contact. with said first terminal, said fuse link being:concurrently urged towards rupture by said spring means.

5. An interchangeable interrupter assembly for a circuit interrupterincluding first second stationary terminals, said interrupter assemblycomprising a tubular member including an arcextinguishing chambersubstantially coextensive therewith, one endof said tubular member beingarranged for releasable pivotable' engagement with the first of saidstationary terminals and having a conducting member positioned proximateto the opposite end thereof, said conducting member being arranged forlatching engagement Withsaid second stationary terminal, two maininterrupter-portions containedwithin said chamber being normally inseries electrical connection with one another and biased towards circuitin terruption, one of said interrupter portions including a movablearcing contact normally in electrical engagement with said conductingmember, an insulating follower member" affixed to one end of saidmovable arcing contact, manually operable; restraining means yieldinglyholding ing member being arranged said movable contact in electricalengagement with said conducting member, the other of said portionscomprising a fusible member adapted to rupture under overload conditionsand arranged for electrical connection with said first stationaryterminal.

6. A circuit interrupter including first and second stationaryterminals, an interrupter assembly normally electrically connecting saidterminals and comprising in combination an insulating tube pivctallypositioned on said first terminal and having an arc-extinguishingchannel substantially coextensive therewith, two main interrupterportions located within said channel and normally electrically connectedwith one another, one of said portions comprising switch means and theother portion comprising a fusible means, said switch means comprising afixed contact adapted to be releasably engageable with said secondterminal, a movable arcing contact slidable within. said channelnormally electrically engaging said fixed contact, an insulatingslidable follower member afllxed to one end of said movable arcingcontact, spring means slidably biasing said movable contact towardselectrical disengagement, and manually operable restraining meansnormally holding said contacts in electrical engagement, said fusiblemeans comprising a fuse linl: adapted to rupture under overload andelectrically connecting said movable contact with said first terminal,said fuse link being concurrently urged towards rupture by said springmeans.

7. An interchangeable interrupter assembly for a. circuit interrupterincluding first and second stationary terminals, said interrupterassembly comprising a tubular member including an arcextinguishingchamber substantially coextensive therewith, one end of said tubularmember being arranged for releasable pivotable engagement with the firstof said stationary terminals and having a conducting member positionedproximate to the opposite end thereof, said conductfor latching engage--ment with said second stationary terminal, a removable protective capmember positioned on and enclosing said tubular member at one endthereof, two main interrupter portions contained within said chamberbeing normally in series electrical connection with one another andbiased towards circuit interruption, one of said interrupter portionsincluding a movable arcing contact normally in electrical engagementwith said conducting member, an insulating follower men ber to one endof said movable arcing contact, manually operable restraining meansyieldingly holding said movable contact in electrical engagement withsaid conducting member, the other of said portions comprising a fusiblemember adapted to rupture under overload conditions and arranged forelectrical connection with said first stationary terminal.

8. A circuit interrupter including first and second stationaryterminals, an interrupter assembly normally electrically connecting saidterminals and comprising in combination an insulating tube pivotallypositioned on said first terminal and having an arc-extinguishingchannel substantially coextensive therewith, a removable protective capmember positioned on and enclosing said tubular member at one endthereof, two main interrupter portions located within said channel andnormally electrically connected with one another, one of said portionscomprising switch means and the other portion comprising a fusiblemeans, said switch means comprising a fixed contact adapted to bereleasably engageable with said second terminal, a movable arcingcontact slidable within said channel normally electrically engaging saidfixed contact, an insulating slidable follower member affixed to one endof said movable arcing contact, spring means slidably biasing saidmovable contact towards electrical disengagement, and normally operablerestraining means normally holding said contacts in electricalengagement, said fusible means comprising a fuse link adapted to ruptureunder overload and electrically connecting said movable contact withsaid first terminal, said fuse link being concurrently urged. towardsrupture by said spring means.

9. A drop-out circuit interrupter construction comprising an upper and alower stationary terminal, an interrupter assembly havingarcextinguishing chamber, said assembly normally electrically connectingsaid terminals and comprising two main interrupter portions containedwithin said chamber, said portions being normally in series electricalconnection with one another, one of said portions being in electricalconnection with said upper stationary terminal, and the other of saidportions being electrically connected to said lower terminal, thefirstunentioned of said interrupter portions comprising a normallyclosed switch means adapted to be opened under load conditions, theother of said main interrupter portions comprising a fusible memberadapted to rupture under overload conditions, said interrupter assemblyadapted to be in latching electrical engagement with said upperterminal, and plural pivot means associated with the interrupterassembly at the lower end for pivotably mounting said tube on said lowerterminal to permit downward and outward r cking motion on rupture ofsaid fusible member.

10. A drop-out circuit interrupter construction including first andsecond stationary term nals, an interrupter assembly normallyelectrically connecting said terminals and comprising in combination aninsulating tube having an arc-extinguishing channel substantiallycoextensive therewith, two main interrupter portions located within saidchannel and normally electrically connected with one another, one ofsaid portions comprising switch means and the other portion comprising afusible means, said switch means comprising a fixed contact adapted tobe releasably engageable with said second terminal, a movable arcingcontact slidable within said channel normally electrically engaging saidcontact, spring means slidably biasing said movable contact towardselectrical disengagement, and manually operable restraining meansnormally holding said contacts in electrical engagement, said fusiblemeans comprising a fuse link adapted to rupture under overload andelectrically con-- necting said movable contact with said firstterminal, said fuse link being concurrently urged to wards rupture bysaid spring and a plural pivot means associated with the interrup er assembly at one end thereof for pivotably mounting said tube on said firstterminal to permit downward and outward rocking motion on rupture ofsaid fusible member.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 2,441,692 Earle May 18, 1948 2,446,676 Yonkers i Aug. 10, 1948

